1. Technical Field
The present invention relates generally to the field of plate-type heat exchangers and specifically to plate-type heat exchangers which provide a cooled or heated surface on which or near which an article to be cooled or heated is placed.
2. Description of the Prior Art
Cooling or heating an object is frequently accomplished by cooling or heating the environment immediately surrounding the object. Thus, the air in a space can be cooled or heated to cool or heat objects therein. In some situations, however, it is advantageous to provide a cooled or heated surface on which the object is placed for transferring heat directly between the object and a heat exchanger. For example, in some types of equipment, such as a missile launcher, batteries providing power for the device must be cooled during use. One advantageous method for cooling the battery is to provide a heat exchanger having a cooled upper surface which will also support the battery. In addition to cooling the battery, such a so-called "cold plate" also serves as a structural support member for the battery. Hence, it is important that, in addition to providing a uniformly cooled surface, the cold plate also has sufficient structural strength to support an object which, in some situations, may weigh hundreds or thousands of pounds.
Other advantageous uses of so-called cold or hot plate heat exchangers having a uniformly cooled or heated surface and sufficient structural strength to support the objects being cooled or heated are also known. For example, such a cold plate heat exchanger could also be used advantageously as the floor or walls of a refrigerated compartment or truck trailer for transporting or storing perishable goods. Curved heat exchangers could be used as side walls of process vessels, such as reactors, fermenters, mixers and the like.
Plate-type heat exchangers known in the past do not provide uniform cooling and/or heating of a surface of the heat exchanger, nor do they provide the structural strength and supportive strength required in the aforementioned applications. U.S. Pat. No. 4,258,784 entitled, "Heat Exchange Apparatus And Method of Utilizing The Same" issued to Clifford R. Perry and Lloyd H. Deitz, discloses a plate-type heat exchanger in which serpentine passages separated by thin plastic sheets are used to transfer heat between two fluids. U.S. Pat. No. 4,006,776 entitled, "Plate Type Heat Exchanger" issued to Robert R. Pfoutz, Anson S. Coolidge, and Derold D. Peter discloses a heat exchanger in which corrugated fin pads are used to enhance heat transfer between a first fluid flowing through passages transversely disposed relative to the direction of the fins in the fin pads and a second fluid flowing through the fin pad. Neither of the patents teach combining the serpentine passages and fin pads for providing a uniformly cooled or heated surface on the heat exchanger, nor do the disclosures teach means for providing exceptional structural and supportive strength in the heat exchanger. Additionally, each teaches transferring heat between two fluids, both of which flow through the heat exchanger.